I think that the suggestion that we might be seeing a number of alternate exhaust layouts is probably highly likely. I have a pet suspicion that they're actually holding off before showing a front loaded exhaust as per Renault, but that's for another thread.
I remembered an image from last season of the floor of the Ferrari which showed channels leading all the way through from the bib right to the top deck of the diffusor. Presumably, these channels fed high pressure air into the diffusor in order to accelerate the air coming from under the car. Obviously this in it's 2010 form would not be allowed (no second deck). Could these tunnels be the 2011 incarnation of these channels?
I was thinking, if they had similar channels all the way from the sides of the bib (or indeed somewhere else perhaps above the step plane) to the back of the car at the location seen here, and be accellerated by the exhaust also exiting into the same channel, before finally emerging just above the diffusor at it's extremeties?
Again, perhaps a sketch would help?
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